Intraluminal, intracavity, intravascular, and intracardiac treatments and diagnosis of medical conditions utilizing minimally invasive procedures are effective tools in many areas of medical practice. These procedures are typically performed using imaging and treatment catheters that are inserted percutaneously into the body and into an accessible vessel of the vascular system at a site remote from the vessel or organ to be diagnosed and/or treated, such as the femoral artery. The catheter is then advanced through the vessels of the vascular system to the region of the body to be treated. The catheter may be equipped with an imaging device, typically an ultrasound imaging device, which is used to locate and diagnose a diseased portion of the body, such as a stenosed region of an artery. For example, U.S. Pat. No. 5,368,035, issued to Hamm et al., the disclosure of which is incorporated herein by reference, describes a catheter having an intravascular ultrasound imaging transducer.
FIG. 1 shows an example of an imaging transducer assembly 1 known in the art. The imaging transducer 1 is typically within the lumen 10 of a guidewire (partially shown), having an outer tubular wall member 5. To obtain an image of a blood vessel, the imaging transducer assembly 1 may be inserted into the vessel. The transducer assembly 1 may then rotate while simultaneously emitting energy pulses, e.g., ultrasound waves, at portions of the vessel from within the vessel and receiving echo or reflected signals.
Turning to FIG. 2, it is known in the art that an imaging console 20 having a display screen, a processor and associated graphics hardware (not shown) may be coupled with the imaging transducer assembly 1 to form a medical imaging system 30. The imaging console 20 processes the received echo signals from the imaging transducer assembly 1 and forms images of the area being imaged. To form the images, the imaging console 20 draws multiple lines, known as “radial lines”, (not shown) on the display screen that each correspond to an angular position of the transducer assembly 1. The processor of the imaging console 20 assigns brightness values to pixels of the lines based on magnitude levels of the echo signals received from the transducer assembly 1 at the angular positions corresponding to the lines. A drawing that includes a large number of these radial lines results in an image such as an intravascular ultrasound (IVUS) image (not shown).
It is further known in the art to continually capture frames of IVUS images while gradually withdrawing the transducer or catheter within a vessel. The resulting stack of frames may be stored and manipulated by the processor, and from these frames, a longitudinal image of the vessel may be generated. In other words, a visualization of the vessel in a plane containing the long axis of the vessel may be rendered, which allows the clinician to assess blockage at different locations along the length of the vessel. For example, U.S. Pat. No. 5,830,145, issued to Tenhoff, the disclosure of which is incorporated herein by reference, describes a system and method for generating longitudinal images of a region of a blood vessel.
The resulting longitudinal image may be used to diagnose abnormalities, such as blockage, within the vessel. A typical treatment known in the art for such abnormalities is the use of one or more stents in the region(s) of interest. Often times, determining the proper size (length and diameter) and position of the stent(s) to be applied within the patient is a “trial and error” type process, which may increase procedure time and risk to the patient. Accordingly, an improved system and method for delivering one or more stents would be desirable.